<template>
  <footer class="footer">
    <!-- This should be `0 items left` by default -->
    <span class="todo-count"><strong>{{unDoneTodoLength}}</strong> item left</span>
    <!-- Remove this if you don't implement routing -->
    <ul class="filters" @click="$emit('switchTodo',type)">
      <li>
        <a href="#/" :class="{selected:type==='all'}" @click="type='all'" >All</a>
      </li>
      <li>
        <a href="#/active" :class="{selected:type==='no'}" @click="type='no'" >Active</a>
      </li>
      <li>
        <a href="#/completed" :class="{selected:type==='yes'}" @click="type='yes'" >Completed</a>
      </li>
    </ul>
    <!-- Hidden if no completed items are left ↓ -->
    <button class="clear-completed" v-if="hasDoneTodo" @click="clear">Clear completed</button>
  </footer>
</template>

<script>
export default {
	data(){
		return{
			type:'all',//no yes
		}
	},
	props:['arr'],
	computed:{
		unDoneTodoLength(){
		return	this.arr.filter(item=>item.isDone===false).length
		},
		hasDoneTodo(){
			return this.arr.some(item=>item.isDone===true)
		}
	},
	methods:{
		clear(){
			if(confirm('确定要删除吗?')){
			this.$emit('clearTodo')
			}
		}
	}
};
</script>

<style>
</style>
